<?php
//ctype_print(mixed $text): bool
//ctype_print — 检测可打印字符

$aa = "aa";
$bb = "aa22";
$cc = "aA\n";

if (ctype_print($aa)) {
    echo '$aa ' . "ok" . PHP_EOL;
} else {
    echo '$aa ' . "no" . PHP_EOL;

}

if (ctype_print($bb)) {
    echo '$bb ' . "ok" . PHP_EOL;
} else {
    echo '$bb ' . "no" . PHP_EOL;

}
if (ctype_print($cc)) {
    echo '$cc ' . "ok" . PHP_EOL;
} else {
    echo '$cc ' . "no" . PHP_EOL;

}
